Direct dynamics simulations with the M06/6-311+ +G(d,p) level of theory were performed to study the (CH2)-C-3 + O-3(2) reaction at 1000 K temperature on the ground state singlet surface. The reaction is complex with formation of many different product channels in highly exothermic reactions. CO, CO2, H2O, OH, H-2 , O, H, and HCO are the products formed from the reaction. The total simulation rate constant for the reaction at 1000 K is (1.2 +/- 0.3) x 10(-12) cm(3) molecule(-1) s(-1), while the simulation rate constant at 300 K is (0.96 +/- 0.28) x 10(-12) cm(3) molecule(-1) s(-1). The simulated product yields show that CO is the dominant product and the CO:CO2 ratio is 5.3:1, in good comparison with the experimental ratio of 4.3:1 at 1000 K. On comparing the product yields for the 300 and 1000 K simulations, we observed that, except for CO and H2O, the yields of the other products at 1000 K are lower at 300 K, showing a negative temperature dependence.